Method of setting woolen textiles



Linn-W;

United States Patent "ice.

2,987,370 METHOD OF SETTING WOOLEN TEXTILES Harold P. Lundgren,Berkeley, Nathan H. Koenig, El

Cerrito, and Clay E. Pardo, Jr., Albany, Calif., assignors to the UnitedStates of America as represented by the Secretary of Agriculture N0Drawing. Filed June 30, 1959, Ser. No. 824,154 4 Claims. (Cl. 8128)(Granted under Title 35, US. Code (1952), see. 266) A non-exclusive,irrevocable, royalty-free license in the invention herein described,throughout the world for all purposes of the United States Government,with the power to grant sublicenses for such purposes, is hereby grantedto the Government of the United States of America.

This invention relates to and has as its primary object the provision ofnovel methods for imparting to woolen textiles durable creases, folds,pleats, or other structural arrangements as may be desired by theoperator.

It is of course well known that garments of all types are provided withsome sort of fabric arrangement, for example, pleats, creases, etc. Suchdeformations are conventionally produced by ironing the garment whileconstrained in the desired pattern. However, these arrangements are buttemporary and when the garment is subjected to wear or is exposed tohumid conditions the creases, pleats, etc. disappear leaving the garmentin a shapeless condition. Materials such as starch are widely employedto obtain more durable creases. However, impregnation of the textilewith starch and similar materials has the drawback that the textile isrendered stiff and harsh so that it does not have the originalcharacteristics of the untreated fabric.

The process of the invention affords many advantages not realized byprior techniques. Some of these advantages are explained below- In thefirst place, the fabric arrangements produced by application of theinvention are durable, that is, they are essentially permanent inpractical consideration. The treated textiles may be subjected tosoaking in cold or even hot water without loss of the structure impartedthereto. Garments treated in accordance with the invention may be wornin the rain or subjected to other humid conditions without loss ofpleats, creases, etc. The treated textiles may be subjected to drycleaning or even washing in conventional aqueous soap or detergentformulations with little detriment to the creases, pleats, or otherarrangements as may be present.

A most significant advantage of the process of the invention is that thedurable arrangements are established without impairing the desirableproperties of the textile. That is to say, such properties as color,hand, elasticity, porosity, resilience, strength, wear-resistance, etc.,are not harmed. For example, textiles treated in accordance with theinvention exhibit essentially the same hand as the original fabric. Thisis in utter contrast to prior processes which depend for theirefiectiveness on the application of shellac, gums, starches, resins, orother high-molecular weight coating materials. In those cases there is asubstantial stiffening of the material so that the original hand of thefabric is impaired. The process of the invention does not involveconstraining the shape of the textile fibers by any coating material butby a chemical rearlatented June 6, 1961 rangement of the structure ofthe fibers into a new structural pattern.

Further items to be mentioned are that the agent used in the process,dimethyl sulfoxide, is inexpensive, commercially-available, andnon-toxic under the conditions of use. Moreover, the process isoutstanding in its utter simplicity and efiiciency.

Another advantage is that the arrangement is set merely by applicationof heat; no oxidizer or other chemical agents as necessary withconventional reducing treatments (e.g., sulphites, thioglycollates,etc.) are needed in the process of the invention.

In applying the process of the invention, dimethyl sulfoxide isdistributed on the textile, the textile is arranged in the desiredpattern, and then while constraining it in such pattern heat is appliedto the arrangement.

The dimethyl sulfoxide is applied as such to the texile or it may bedissolved in a volatile, inert liquid solvent and the solution appliedto the textile. Where a solvent is employed, water is preferred as beingthe most convenient and economical solvent. The dimethyl sulfoxide maybe applied over the entire surface of the textile as by immersion,brushing, spraying, etc. Usually, however, it is preferred to apply thiscompound only to the area where the fibers are to be deformed. Forexample, in treating trousers in accordance with the invention, thedimethyl sulfoxide is applied in a stripe or line along the length ofthe legs of the garment where the creases will be formed. It is obviousthat by applying the compound only along the line where the textile isto be deformed there results a substantial saving in the amount ofdimethyl sulfoxide which is required for the process.

The amount of dimethyl sulfoxide applied to the textile is not critical.Dimethyl sulfoxide exhibits a very potent effect in enabling theformation of durable textile arrangements and any amount thereof appliedto the textile will result in significant improvement over conventionalcreasing, pleating, or other type of fiber deformation produced bypressing with a hot iron or similar device. Also, there is no harm inusing too much dimethyl sulfioxide as any excess is vaporized in theheat treatment.

As stated above it is preferred to apply the dimethyl sulfoxide along aline where the crease, pleat, or other configuration is to be formed.With such method of application, the amount of dimethyl sulfoxide may bereckoned on the basis of volume per unit of linear distance. On thisbasis, then, it is preferred to deposit dimethyl sul foxide in an amountof at least 0.0005 ml. per inch. More preferably to attain especiallydurable deformation the amount is at least 0.1 ml. per inch. As notedabove, no harm is done by using excessive amounts of dimethyl sulfoxide;any excess being vaporized in the heating step.

After applying dimethyl sulfoxide to the textile, the textile isarranged in the desired pattern. The arrangement may involve suchmanipulations as folding over sections of the textile, creasing,pleating, or shaping on suitable mandrels or dies. For example, inapplying the process to garments, these articles are laid on a flatsurface with the desired areas folded over, creased, or otherwisearranged as conventional in preparing garments for pressing. Where morecomplex configurations are involved the textile may be compressedbetween dies having the desired shape. For example, ribbed effects maybe obtained by constraining the fabric between dies havapplied duringthe heating step.

a the selected pattern.

ing corrugated surfaces; pleated eifects may be obtained by constrainingthe fabric between dies having mating V-shaped projections. Yarns may becrimped by compressing between corrugated surfaces. Further extensionsof these principles will be obvious to those versed in the textile art.

In any event, the textile while constrained in the arranged pattern issubjected to heat to set the textile fibers in the selected pattern. Theheat treatment, or curing as it may be termed, is generally accomplishedby contacting the textile with steam or with heated platens, rollers,dies, or the like. Also, the textile may be placed in an oven orsubjected to radiation from infrared heaters or the like. For theestablishment of pleats, creases and the like a conventional tailorssteam press is quite satisfactory as the textile can be subjected todirect contact with steam while held in the selected pattern by thepress platens. Generally, the heating, whether by steam or a hot roller,die, platen, etc., is at about 85 to 150 C. The time for cure isdecreased with increasing temperature. Usually, the textile is properlycured when the odor of dimethyl sulfoxide essentially disappears.Depending on the temperature the time for cure will be on the order of0.5 to 15 minutes. In any particular case, pilot trials may be conductedwith different heating times and noting the durability of thearrangements in the treated textile by soaking it in water and observingits appearance. From such trials it is simple to determine the propertime of heating for the main batch of textile to be treated. Usually,however, it is unnecessary to conduct such trials by simplydiscontinuing the heating when the odor of dimethyl sulfoxide isessentially negligible. Generally it is preferred to heat the dimethylsulfoxide-treated textile at a temperature of about from 140 to 145 C.,in which case the deformation is set in about 3 to 5 minutes. Also,heating by direct contact with steam is generally preferred as thepenetration of the steam into the textile causes faster heating of thetextile than is obtained with the case of hot platens, rollers, dies, orthe like. Of course, a faster heating of the textile means that the timefor setting is reduced.

The theory of the process is imperfectly understood. However, it isbelieved that during the heat treatment in the presence of dimethylsulfoxide, certain chemical bonds in the wool molecule are disrupted andthen reformed into new patterns. By this molecular re-orientation thefibers are set in the position in which they are constrained during theheat treating step.

The sequence of the operations of (a) application of the dimethylsulfoxide and (b) mechanical arranging of the textile is not critical.Thus the textile may be treated with dimethyl sulfoxide, shaped to thedesired pattern and heated while constrained in such pattern. On theother hand the textile may be shaped to the desired pattern, thedimethyl sulfoxide applied, and the textile heated while constrained insuch pattern. Moreover, although it is preferred to apply the dimethylsulfoxide to the textile prior to the heating step, this agent may beFor example, the textile may be arranged-into the desired pattern, thensubjected to direct contact with a current of steam containing dimethylsulfoxide while the textile is constrained in In a preferredmodification of the invention, the textile material, prior toapplication of dimethyl sulfoxide, is Wetted with water. In this way thearrangement eventually produced is especially resistant to water, humidconditions, and washing. In carrying out this procedure the textile issoaked in water until it is thoroughly wet thereby. This point can bereadily determined by dropping water on the textile. When it is wet, theWater will soak into the textile instead of running off in droplets. Toassistin wetting the textile, a conventional Wetting agent may be addedto the water. Suitable for this purpose are such agents as for example:Soaps, long-chain alkyl sodium sulphates or sulphonates, long-chainalkyl benzene sodium sulphonates, esters of sulphosuccinic acid, etc.,typical examples being sodium oleate, sodium lauryl sulphate, sodiumdodecane sulphonate, sodium alkyl (C -C benzene sulphonate, sodiumdioctylsulphosuccitrate, etc. Agents of the nonionic type may be usedfor example the reaction products of ethylene oxide with fatty acids,polyhydric alcohols, alkyl phenols and so forth. Typical of such agentsare polyoxyethylene stearate, polyoxyethylene ethers of sorbitanmonolaurate, isooctyl phenyl ether of polyethylene glycol, etc. Cationicagents may also be used as for example long-chain alkyl trimethylammonium chlorides, bromides, and methosulphates. Only a smallconcentration of Wetting agent is needed, i.e., about 0.05 to 0.5% byweight. After the textile is wet it is heated in the presence ofdimethyl sulfoxide while constrained in the desired pattern asheretofore described.

The process of the invention may be applied to wool textiles in the formof threads, fibers, yarns, slivers, rovings, woven fabrics, knittedfabrics, felts, or garments made of woven or knitted fabrics. Thetextiles may be white or dyed goods. Typical applications of theinvention are: to provide garments with pleats, creases, or otherarrangements customary in tailoring; to provide sheets of fabric withpre-formed pleats so that the product may be used for the fabrication ofskirts, draperies, etc.; to produce crimp, twist, or other configurationin yarns, threads and the like. Further applications of the inventionwill be obvious to those skilled in the art from the aboveillustrations.

The invention is further demonstrated by the following illustrativeexamples:

Example I A section of 10.5 oz. wool flannel was cut into strips 50 cm.long and 4 cm. wide. Each strip was then folded in accordion fashion toprovide seven pleats along the length of each strip.

Several batches of the folded strips were then treated with dimethylsulfoxide. In the treatment, this compound was applied along the line ofeach fold in an amount of about 0.1 ml. per inch. To provide controls,several batches of the folded strips were not treated.

The treated and untreated strips, in the folded form, were placed in atailors steam press. There they were pressed for 3 minutes whilesubjected to direct contact with steam at about 140-145 C. Aftersteaming, the press platens were subjected to vacuum for a minute toexhaust steam from the cloths.

To test the durability of the pleats, the following procedure wasemployed: After steam pressing each strip was suspended vertically byone end and the length of the strip (L) under its own weight thenmeasured. The strips were then soaked to ascertain the permanence of thepleats. The soaking involved holding the strips for one minute in water,at room temperature, containing 0.1% of a wetting agent (Triton X-100,iso-octylphenyl ether of polyethylene glycol). After this soaking thestrips were air-dried then suspended as before and their length (L')measured. vThe percentage permanence of the pleats is then obtained fromthe formula 50-L Percentage permanencex It was also observed that thedimethyl sulfoxide-treated strips even after soaking had' sharp,well-defined pleats. The control strips after soaking retained only ageneral sinuousness with no distinct pleats.

Example II A x 5 cm. piece of aluminum sheet was punched with severalholes having a diameter of 7 mm. A piece of wool cloth was placed onthis template and the portions of the cloth over the holes were pressedthrough the holes to provide an embossed effect. The areas of clothprojecting through the holes were secured in place by running a wirethrough the material. The projecting areas of the cloth were then wetwith dimethyl sulfoxide. The assembly was then subjected to steam for 3minutes at about l40l45 C. The fabric was removed from the template,soaked for one minute in water containing 0.1% Triton X-100, then driedin air. It was observed that the cloth retained the embossed design. Acontrol test wherein all the steps were applied except application ofthe dimethyl sulfoxide, yielded a cloth which displayed no evidence ofthe embossing.

Example III Dimethyl sulfoxide was applied from a burette along a linetraced on a piece of wool cloth (6.9 oz. per sq. yd.), applying about0.1 ml. of dimethyl sulfoxide per inch. Several cloths were treated inthis way, then each was folded over along the line where the dimethylsulfoxide was applied and pressed in a tailors steam press. Thetemperature of the steam supplied to the press was 140l45 C. In eachcase, the cloths were pressed for 3 to 5 minutes while steam was flowingout of the press platens onto the cloths. The flow of steam was then cutoil and suction applied to the platens to exhaust steam fiom the cloths.Suction was applied for a minute.

The cloths were then removed fiom the press. It was observed that thecreases were sharp. To test the durability of the creases, the clothswere soaked one minute in water containing 0.1% of a wetting agent(Triton X-lOO, iso-octylphenyl ether of polyethylene glycol) at roomtemperature. The cloths were dried in air and the soaking and dryingrepeated two more times. A control sample which was not treated withdimethyl sulfoxide but which was steam pressed as were the other sampleswas also subjected to the soaking tests.

After each soaking and drying, the cloths were exam- The procedure setforth in Example III was repeated except that in these runs, aqueoussolutions of dimethyl sulfoxide were used instead of this compound assuch.

The conditions and results are tabulated below:

Concentration of Application Crease rating dimethyl sulfoxide ofdimethyl Time of in treating solution, sulfoxide, steaming, percent(vol. basis) inL/inch min. After 1 After 3 soak soaks 0.095 3excellentgood. 0.095 5 o Do. 0.05 3 good fair. 0. 05 5 excell nt Do.0.005 3 fair". Do. 0. 005 5 Do.

Samples of wool cloth were soaked in water containing 0.1% Triton X-until the wool was thoroughly wet. The cloths were folded over and steampressed for 2 minutes. The cloths were then unfolded and dimethylsulfoxide was then applied along the line of each crease at the rate ofabout 0.1 ml. per inch. The cloths were then folded over again andpressed with steam at about 145 C. for 5 minutes.

To test the durability of the creases, the cloths were soaked for 1minute in water containing 0.1% Triton X-100 then dried in air. Thecloths were then further subjected to repeated soaking under the sameconditions with drying between each soaking. In one series, the soakingwater was at 25 C., in another the soaking water was at 100 C. Theresults are tabulated below:

It was also observed that the creases in the treated samples remainedintact when the cloth samples were dry cleaned by the method 25-52AATCC.

Having thus described the invention, what is claimed 1. A method forimparting a stable set to wool textile material which comprises applyingdimethyl sulfoxide to a wool textile, arranging the textile into apredetermined pattern, and while constraining it in such patternsubjecting it to heat to set it in the predetermined pattern.

2. A method of imparting a stable set to wool textile material whichcomprises applying dimethyl sulfoxide to a selected area of a wooltextile where the fibers are to be deformed, arranging the textile todeform said fibers according to a predetermined pattern and whileconstraining the fibers in such pattern, subjecting them to heat to setthe fibers in the deformed position.

3. A method for imparting a stable set to wool fibers which comprisesheating wool fibers in the presence of dimethyl sulfoxide while the woolfibers are constrained in a predetermined pattern.

4. A method for imparting a stable set to wool fibers which comprisesapplying steam to wool fibers in the presence of dimethyl sulfoxidewhile the wool fibers are constrained in a predetermined pattern.

Houtz: Textile Res. 1., pp. 786-801, November 1950. Vickerstafi, Thomas:The Physical Chemistry of Dyeing, Intersci. Pub., Inc., N.Y.C., 1954,pp. 489, 492.

1. A METHOD FOR IMPARTING A STABLE SET TO WOOL TEXTILE MATERIAL WHICHCOMPRISES APPLYING DIMETHYL SULFOXIDE TO A WOOL TEXTILE, ARRANGING THETEXTILE INTO A PREDETERMINED PATTERN AND WHILE CONSTRAINING IT IN SUCHPATTERN SUBJECTING IT TO HEAT TO SET IT IN THE PREDETERMINED PATTERN.